The following text comes from the official BO2 website.  Much of it would later be reworded for the manual.  Images were...enhanced.

Blood Omen 2 takes place four hundred years after the original Legacy of Kain: Blood Omen, in which the vampire Kain chose to rule the world of Nosgoth in its damnation, rather than die for its salvation. 

Since the events of that period in time, Kain had become the powerful commander of an army fixated on ruling the Land of Nosgoth.  In response to his ascension to power, another faction known as the Sarafan appeared in the land.  The Sarafan are a group of militant and zealot humans led by a mysterious and potent figure, known only as the Sarafan Lord.  Determined to wipe out the vampire scourge, the Sarafan clashed with Kain’s army.  In the final battle, the Sarafan Lord defeated Kain in mortal combat, stripped him of his macabre blade the Soul Reaver, and tossed him off a cliff into an abyss of appearant demise.

Yet this was not to be so.  Pure and true wickedness of Kain‘s ilk cannot be expunged so easily.

After more than 200 hundred years drifting in a void of unconsciousness, Kain groggily awakens in a strange place with almost no memory of his former self.  Another vampire named Umah, had taken him in and revived him to health after Kain’s little recollected and deadly battle with the Sarafan Lord.  He is weak, and has lost most of his former formidable powers.  Worse still, his trusted weapon the Soul Reaver is missing.  As Kain regains presense in the waking world, Umah begins to fill him in on the events of recent past, while fragments of Kain’s shattered memory return.

Umah recounts to Kain that when his torn body was found, it was revived and brought to the capitol of Nosgoth, the city of Meridian.  In the two centuries that Kain has been dormant in hibernation, the Sarafan have risen and taken fascist control over most of Nosgoth.  Far from the great empire they once embodied, the Vampires now exist only as a small resistance to the Sarafan, called the Cabal, in Meridian.  It is into this resistance that Kain emerges and is now, by brotherhood and lust for vengeance, a part of.  The ambition of the resistance is simple: slay the Sarafan Lord, and the Sarafan Order will crumble.

Because the Sarafan have no knowledge Kain’s existence, he is the perfect agent to locate and kill the Sarafan Lord.  Kain agrees to help the Cabal for the time being, until which time he sees fit to follow his own agenda, and seek revenge at all cost…

SARAFAN LORD

Kain’s most powerful nemesis is the evil warlord who controls Nosgoth’s capital city, Meridian. It was Sarafan Lord himself who, 200 years ago, resurrected the Sarafan armies and defeated Kain.

 

FAUSTUS

The first of the enemy vampires Kain meets, Faustus dwells in the Smuggler’s Den.

SEBASTIAN

An old vampire acquaintance of Kain’s, Sebastian is now helping The Sarafan. Seek him out in the Industrial Quarter.

MARCUS

Another of the traitorous vampires working with The Sarafan, Marcus can be found in the Upper City. Beware his psychic abilities.

 

THE SEER

No one knows the origins of this mysterious witch living in the Canyons.

 

MAGNUS

Being held forever inside the Eternal Prison, Magnus has gone mad. Kain must defeat him before he can escape

 

 

Some of these bios come from the BO2 game manual. Others come from the official BO2 website.

Peasant

These are the regular denizens of Nosgoth.  Mostly, they are pretty much fodder – fresh blood for Kain to feast on but Kain can also learn a lot from listening to their conversations.  Kain may overhear secret information that he can use later.

Thief

Ninja-like assassins that prefer to hide in the shadows and surprise Kain with a surprise attack.  Their weapon of choice is the dagger, and they are quite nimble.  If close to death, the thief will always try to run away.

Guard

These are the basic guards of the Sarafan.  They will attack Kain on sight.

 

Eyeless Wretch

Some of the poor inmates of the Eternal Prison.  No one knows how old they are or how long they’ve been in the prison but their eyes have been sewn shut.  Don’t expect them to be aggressive at all.  Don’t expect any information from them either.

Prison Guardian

The Guardians run the Eternal Prison.  These scythe-wielding creatures will talk big and may try to back it up with an ambush later in the level.

 

Demon Spider

Giant spider creatures that appear later in the game.  Apparently, their size their size is due to exposure to Glyph energy.  These creatures generally hunt in packs and cannot be grabbed nor thrown by Kain – though he can still suck their blood.